Prior art methods and systems used for reinforcing a portion of a structural member utilize either a foamable material placed in contact with the selected structural member or a combination carrier and foamable material, which can be placed or attached to targeted portions of a structural member to achieve structural reinforcement and enhance structural rigidity. Although such prior art methods and systems work well and are advantageous in many applications, the structural nature, weight, or cost of the carrier may limit the effectiveness for which the system could be used. For instance, the structure, location, and geometric volume of the structural member being reinforced can make it difficult or place constraints on the ability to insert a carrier. In addition, the weight of the carrier itself may cause additional issues of economic efficiencies in the manufacturing process, particularly when used to reinforce structural members having large interior volumes, such as an automotive frame or rail member. Thus, this method provides an alternative system and method that will provide structural reinforcement utilizing lightweight reinforcement components which can be introduced to the vehicle at various stages throughout the manufacturing or assembly process concerning the member being reinforced.
The present invention obviates and overcomes the drawbacks found in the prior art by providing a hollow carrier that is formed through either a blow molding, rotational molding, or other processes to create a hollow structure that fit within the contours of an inner portion of the chosen structural member upon insertion into the structural member. The system may comprise one or more carriers that can be filled with a rigid, low density material specifically selected for characteristics that include reduced weight and reinforcement capabilities in addition to low overall cost. The hollow carrier, although preferably rigid, can also be flexible and has an inner volume having a variety of geometric dimensions and expansion volumes. The hollow carrier is suitable and capable of receiving a variety of materials, which may or may not be expandable or heat-activatable, that can be pumped, placed, pellet-fed, extruded, retained, or otherwise disposed within the carrier for structural reinforcement, damping, and/or sealing of the member without allowing unwanted spillage or leakage of the material to portions of the structural member such as tooling holes and other hardware needed in the manufacturing process. It should be understood that in certain applications filling is not necessary. The carrier is further defined by an exterior shell or surface, which can be placed directly into contact with the selected portion of the structural member targeted for reinforcement. A heat-activated structural material, psa, bonding agent, or other adhering material is applied to at least a portion of the exterior shell or surface of the carrier to bond and adhere the now filled carrier in place to the structural member during exposure to the cure ovens and other operations typically encountered in an automotive manufacturing facility.